http://www.eveonline.com/devblog.asp?a=blog&bid=907

Basically CCP are going to offer a choice of 30 days gametime or a PLEX when inviting a player via the buddy program - they're also increasing the invite limit to ten per month

Lastly according to the article a quarter of all new players come in via the buddy program - thats a lot of alts by my estimation!